The pathogenesis of necrotic enteritis in chickens: What we know and what we need to know. Review.

The pathogenesis of necrotic enteritis in chickens: What we know and what we need to know. Review. Avian Pathol. 2016 Jan 26;:1-21 Authors: Prescott JF, Parreira VR, Mehdizadeh Gohari I, Lepp D, Gong J Abstract This review summarizes advances in understanding the pathogenesis of necrotic enteritis (NE) of chickens caused by netB-positive Clostridium perfringens. The discovery of NetB as the essential toxin trigger for the disease was followed by recognition that it forms part of a large plasmid-encoded 42 kb pathogenicity locus (NELoc-1). While the locus is critical for toxin production, it likely has additional functions related to colonization and degradation of the mucus barrier, which are essential both to multiplication and to bringing NetB close to the intestinal epithelium. Two "chitinases" (glycoside hydrolases) present on NELoc-1 are predicted to be involved in mucin degradation, as is the large carbohydrate binding metalloprotease, shown to be involved in mucinase activity in other clostridia. A second pathogenicity locus found in netB-positive C. perfringens, NELoc-2, also encodes a glycoside hydrolase likely involved in mucin degradation. Upon reaching a sufficient cell density on the intestinal mucosa, the Agr-like quorum-sensing system is triggered, which in turn up-regulates the VirR/VirS regulon. This regulon includes NetB. Where NetB initiates damage is unresolved, but it may be deep in the intestinal mucosa, rather ...
Source: Avian Pathology - Category: Pathology Authors: Tags: Avian Pathol Source Type: research